1. Field
Embodiments disclosed herein relate to a heavy load handling carriage which enables transfer of a heavy load, such as a probe card, under various working environments.
2. Description of the Related Art
In general, a semiconductor fabrication process passes through various process equipment which process a wafer according to various methods. After the fabrication process of the wafer has been completed, a test process to identify defective chips from among the semiconductor chips formed on the wafer is carried out before packaging of the semiconductor chips. Since such a test process is carried out in a tester, the wafer to be tested must be loaded into or unloaded from the tester. Therefore, to perform the test process the wafer is accommodated in an exclusive test jig, i.e., a probe card.
Since such a probe card generally has a weight of 20 kg or more, if a worker manually transfers the probe card from a stocker in which probe cards are stored to the tester, the worker is burdened and thus an exclusive or specialized carriage may be used.
However, various types of equipment may be densely disposed on a semiconductor fabrication line, and thus a moving space may be limited and narrow or a duct forming a stepped structure may be formed in the moving space according to the circumstances and layout of the semiconductor fabrication line.
Therefore, there is an increasing need for development of a carriage capable of transferring a heavy load, such as a probe card, in a semiconductor fabrication line which has a complicated structure.